Tread member for antiskid devices



Nov. 14, 1939. H. A DELANO TREAD MEMBER FOR ANTISKID DEVICES Filed April 2, 1937 BY W ATTORNEY Patented Nov. 14, 1939 UNITED .sTArEs 2,180,099 TREAD MEMBER FOR AINTIYSKID DEVICES Howard A. Delano, vSpringettsbury Township, York County, Pa., assignor to American Chain & Cable Company, Inc., New York, N. Y., a corporation of New York Application April 2, 1937, SeriaI -No. 134,471 18 Claims. (01. 152-245) The present invention relates to antiskid devices and has for an object to'provide improvements in tread members therefor.

The invention relates more especially to' tire chains comprising tread links of round stock each having the form-of an elongated closed loop, and an object of the inventionis to reinforce such a tread link by connecting the side strands of the link with a caulk of semi-round stock bent to provide a pair of legs which flare outwardly from the road face of the link and transversely with respect to the longitudinal axis of the link. The term semi-round is used in this specification and the claims to denote stock that 'is 15 substantially fiat on one side and rounded on the opposite side, and the term will be understood to include not only half-round stock, but other stock as Well which in cross-section has substantially the form of .a segment of a circle. 20 A more specific object of the invention is to provide a tread link with an arch shaped caulk disposed transversely to and seated between the side strands of the link, with the fiat side of the semi-round stock on the inner periphery of the 25 arch. v

In the preferred form of my invention the link is of curb type and the free ends of the caulk project from the road face of the link beyond the road engaging lobes of the link. 3 Preferably, the caulk is disposed ina transverse plane lying at an oblique angle to the longitudinal axis of the link, although it is also within the scope of my invention to set the caulk in a plane normal to said axis. 35 Since the outer face of the caulk is transversely rounded it is particularly adapted to be seated against the oppositely inclined side strands of the link at any desired angle to the longitudinal axis of the link, because in every case it will 40 make tangential contact with the side strands. Preferably, the diameter of the semi-round stock is greater than that of the link stock, so that a relatively broad caulk may be used, and the free ends of the caulk may be cut. to formextended knife edges adapted to dig into the road surface.

Preferably the caulk is case hardened and .because of its semi-round cross-section a greater proportion of its cross-sectional area will be 50 hardened than would be possible if round stock were used.

Other objects and advantages of my invention will appear in the following description of certain embodiments thereof and thereafter the novelty and scope of the invention will be pointed out in the claims.

In the accompanying drawing:

Figure 1 is a view in side elevation of a prec4) ferred form of treadlink equipped with my lme proved caulk, the caulk being shown in ground engaging position;

Fig. 2is'a bottom plan view of the same;

Fig. 3 is an end view of the same;

Fig. 4 is a bottom plan view of a tread member similar to thatshown in Figs. 1 to 3 inclusive, but with-the caulk oppositely inclined;

Fig. 5 is a bottom plan view of still another form of tread member in which the caulk is disposed in a plane normal to the longitudinal axis of the link; I

Fig. 6 is a view in cross section taken on the line 66 of Fig.5; and

Fig. 7 is a view in cross section of a curb link with a different form of caulk welded thereto,-

showing also the relation of the link to a deeply I grooved tread portion of a tire.

In the drawing, I have illustrated individual chain links, but it will be understood that in practice any desired number of these links may be interlinkedto form the tread portion of a cross-chain in a tire chain assembly. In the following description and in the claims the link Will be considered as in road-engaging position and 'the-terms downward and upward are used with reference to such position-of the link.

The tread member shown in Figs. 1 to 3 comprises a curb link Ill having a pair of oppositely inclined side strands II and [2, respectively, said side strands being connected at opposite ends thereof by oppositely inclined end portions l3 and M, to form an elongated loop- The link has a pair of diagonally opposed, upwardly projecting, tire-engaging lobes l5 and I6, respectively, and a pair of diagonally opposed downwardly projecting-lobes I1 and [8 adapted to engage the road surface. However, a caulk tends to raise these lobes l1 and I8 above the road R, as indicated in Fig. l.

The caulk zll-which has the form of an arch, is seated between the side strands of the link and is welded to said side strands. The caulk is made of semi-round stock, or, in other words, the stock in cross-section has the form of a segment of a circle comprising a rounded outer surface 2| and a flat inner surface 22. Preferably, the rounded surface M has a greater radius than the stock of which the link is made. The free end faces 23 of the caulk are disposed radially with respect to the center of the arch and form knife edges 24 that project below the lobes I1 and Ill. The caulk 20 lies in a plane that is oblique to the longitudinal axis of the link and the knife edges 24'lie adjacent the lobes l1 and I8.

Because of the transversely rounded outer surface of the caulk, the latter will make a point contact with each strand of the curb link, this point contact being extended into a broad weld spot when the caulk is welded to the link. Were the caulk provided with a flat outer face it would have to be twisted to provide a fiat bearing against the oppositely inclined side strands of the link, but such twisting is obviated by employing semi-round stock. After the caulk is welded to the link it is case hardened and because the caulk is of semi-round cross-section it will be obvious that a much greater proportion of its cross-sectional area will be hardened than would be the case were the caulk of round crosssection.

In service, knife edges 24' will cut into ice and other slippery road surfaces increasing traction and preventing slippage. It will be observed that the knife edges 24 are disposed at an angle to the transverse axis of the link and hence they will resist any tendency ofthe vehicle Wheel to slip sidewiseas well as in its normal plane of rotation. A large part of the vehicle load will be supported by the lobes IT and 8 since the knife edges will in most cases penetrate the road surface sufficiently to provide contact between the lobes I1 and I8 and said road surface.

The construction shown in Fig. 4 differs from that shown in Figs. 1 to 3 in the position of the caulk, and consequently, corresponding parts in Fig. 4 will be indicated by the same reference numerals with a suffix a. The caulk 20a is disposed at an angle to the longitudinal axis of the link We, but the direction of inclination is reversed with respect to that of caulk 20 in Fig. 2, so that the knife edges 24a lie adjacent the tire engaging lobes l5a and Mia and remote from the ground engaging lobes Ha and Ma. The caulk a. is also of greater length than the caulk 20 so that although it is welded to the link at higher points on the side strands Ila and l2a the knife edges will project below the level of the ground engaging lobes ila and l8a. With this link a four point contact with the road is provided by the two knife edges 2 3a. and the two lobes Na and 18a.

The construction shown in Figs. 5 and 6 is also similar to that shown in the previous figures except for the position of the caulk, and corresponding parts are therefore indicated with the same reference numerals bearing the suffix b. The caulk 20b is disposed in a plane normal to the longitudinal axis of the link and the knife edges 24a, therefore, lie parallel to said axis. This construction is well adapted to prevent slippage of a wheel in its plane of rotation, but since the knife edges parallel the longitudinal axis of the link and hence are disposed at right angles to the plane of rotation of the wheel they are not as well adapted to prevent side slippage. However, it will be understood that when a vehicle wheel skids laterally it has a forward component due to the momentum of the vehicle so that even though the knife edges 26 are disposed at right angles tothe normal direction of travel of the vehicle they will offer considerable resistance to side slippage of the wheel.

While I prefer to use the arch type of caulk my invention is not limited to this type. Thus, in Fig. 7, I show a caulk 200 of semi-round stock which is bent to form an inverted V with the apex thereof projecting between the side strands He and We of the curb link [00. The drawing illustrates the link in transverse section, and hence only one of the tire-engaging lobes, I50, and one of the road-engaging lobes, We, are shown. The caulk, as shown, lies in a plane normal to the longitudinal axis of the link, but it may incline from normal either in the direction shown in Fig. 2, or that shown in Fig. 4.

It will be noted that the apex 25 rises above the side strands and reaches approximately to the level of the tire-engaging lobes. The purpose of this is to provide another tire-engaging point between said lobes, thus partly filling the opening in the link between the lobes. It is common practice today to provide rubber tire treads with ribs intersected by deep transverse grooves. When an antiskid chain is applied to such tires, there is a tendency for the crosschain links to catch in such grooves, particularly at the outer edges of the tire tread. A side strand may drop into a transverse groove and lock the chain against creeping, whereupon each time the cross chain is run over, the hooks which connect the cross chain to the side chains will rub up and down on the side walls of the tire, eventually wearing through to the canvas. Such injury to a tire is prevented by the construction shown in Fig. 7, because the additional intermediate support for the tire provided by the apex 25 of the caulk prevents the side strands from entering and catching in the tread grooves. A fragment of the tread portion of a tire is shown at 26, and the transverse grooves therein are shown at 21. It will be evident that with the parts in the position illustrated, the side strand llc, although directly under one of the grooves 21, will not be forced into the groove because of the support provided by the part 25 of the caulk in cooperation with the upwardly projecting lobe (not shown) diagonally opposite the lobe 150.

While I have described a preferred embodiment of my invention and certain modifications thereof it will be understood that these are to be taken as illustrative and not limitative and that I reserve the right to make various changes in form, construction and arrangement of parts without departing from the spirit and scope of my invention as set forth in the claims.

I claim:

1. An antiskid device comprising a tread link in the form of an elongated closed loop, and a caulk of semi-round stock disposed transversely to the longitudinal axis of the loop and welded to the side strands of the link, said caulk having a pair of down-turned legs flaring apart and projecting below the road face of the link with a fiat face of the stock at the inner side of said legs.

2. An antiskid device comprising a tread link in the form of an elongated closed loop, and a caulk of semi-round stock bent to provide a pair of legs flaring apart, with the fiat face of the stock at the inner side of the legs, said caulk being disposed in a plane transverse to the longitudinal axis of the loop with the central portion of the caulk seated between and welded to the side strands of the link and the legs projecting below the road face of the link.

3. An antiskid device comprising a tread link in the form of an elongated closed loop of round stock, and a caulk of semi-round stock disposed transversely to the longitudinal axis of the loop and welded to the side strands of the link, said caulk having a pair of down-turned legs flaring apart and projecting below the road face of the link with the fiat face of the caulk stock at the inner side of said legs, said flat face being of greater width than the diameter of the link stock, and each leg terminating at its free end in a knife edge coincident with said flat face.

4. An antiskid device comprising a tread link in the form of an elongated closed loop, and an arch shaped caulk of semi-round stock disposed in a plane transverse to the longitudinal axis of the loop with the central portion of the caulk seated between and welded to the side strands of the link and the free ends of the caulk projecting below the road face of the link, the flat face of the stock being at the inner side of said legs.

5. An antiskid device comprising a tread link in the form of an elongated closed loop of round stock, and an arch shaped caulk of semi-round stock disposed in a plane transverse to the longitudinal axis of the loop with the central portion of the caulk seated between and welded to the side strands of the link and the free ends of the caulk projecting below the road face of the link, the flat face of the caulk stock being at the inner side of said legs and being of greater width than the diameter of the link stock, and each free end being formed with a knife edge coincident with said flat face.

6. An antiskid device comprising a tread link of curb type, and a caulk of semi-round stock disposed transversely to the longitudinal axis of the link and welded to the side strands of the link, said caulk having a pair of down-turned legs flaring apart and projecting below the road face of the link with the flat face of the stock at the inner side of said legs.

7. An antiskid device comprising a tread link of curb type, and a caulk of semi-round stock disposed transversely to the longitudinal axis of the link and welded to the side strands of the link, said caulk having a pair of down-turned legs flaring apart and projecting below the road face of the link with the flat face of the stock at the inner side of said legs, each leg terminating at its free end ina knife edge coincident with said fiat face.

8. An antiskid device comprising a tread link of curb type, and a caulk of semi-round stock bent to provide a pair of legs flaring apart With the flat face of the stock at the inner side of the legs, the central portion of the caulk being seated between and welded to the side strands of the link and the legs projecting below the road face of the link, said caulk lying in a plane normal to the longitudinal axis of the loop.

9. An antiskid device comprising a tread link of curb type, and a caulk of semi-round stock 'bent to provide a pair of legs flaring apart with the flat side of the stock at the inner side of the legs, said caulk lying in a plane transverse to the longitudinal axis of the link with the central portion of the caulk seated between and welded to the side strands of the link and the legs projecting below the road face of the link, the flat face of the caulk stock being of greater width than the diameter of the link stock.

10. An antiskid device comprising a tread link of curb type, and a caulk of semi-round stock bent to provide a pair of legs flaring apart with the flat face of the stock at the inner side of the legs, the central portion of the caulk being seated between and welded to the side strands of the link and the legs projecting below the road face of the link, said caulk lying in a plane oblique to the longitudinal axis of the link with the free ends of the legs adjacent the road-engaging lobes of the link.

11. An antiskid device comprising a tread link of curb type, and a caulk of semi-round stock bent to provide a pair of legs flaring apart with the flat face of the stock at the inner side of the legs, the central portion of the caulk being seated between and welded to the side strands of the link and the legs projecting below the road face of the link, said caulk lying in a plane oblique to the longitudinal axis of the link with the free ends of the legs remote from the road-engaging lobes of the link.

12. An antiskid device comprising a tread link of curb type, and an arch shaped caulk of semiround stock with the central portion of the caulk seated between and welded to the side strands of the link, the free ends of the caulk projecting below the road face of the link with the flat face of the stock at the inner side of said legs, said caulk being disposed in a plane normal to the longitudinal axis of the link.

13. An antiskid device comprising a tread link of curb type, and an arch shaped caulk of semiround stock disposed in a plane transverse to the longitudinal axis of the link, with the central portion of the caulk seated between and welded to the side strands of the link and the free ends of the caulk projecting below the road face of the link, the flat face of the stock being at the inner side of said legs, and being wider than the diameter of the link stock, each free end terminating in a knife edge coincident with said flat face.

14. An antiskid device comprising a tread link of curb type, and an arch shaped caulk of semiround stock with the central portion of the caulk seated between and welded to the side strands of the link, the free ends of the caulk projecting below the road face of the link with the flat face of the stock at the inner side of said legs, said caulk lying in a plane oblique to the longitudinal axis of the loop with the free ends of the caulk adjacent the road-engaging lobes of the link.

15. An antiskid device comprising a tread link of curb type, and an arch shaped caulk of semiround stock with the central portion of the caulk seated between and welded to the side strands of the link, the free ends of the caulk projecting below the road face of the link with the flat face of the stock at the inner side of said legs, said caulk lying in a plane oblique to the longitudinal axis of the loop with the free ends of the caulk remote from the road engaging lobes of the link.

16. An antiskid device comprising a tread link of curb type, and a caulk disposed in a plane transverse to the longitudinal axis of the link, said caulk being formed of semi-round stock transversely bent to provide a pair of integrally connected legs seated between the side strands of the link and welded thereto with the flat face of the stock on the inner side of said legs, the legs flaring apart and projecting below the road face of the link and that portion of the caulk integrally connecting the legs projecting upwardly between the side strands approximately to the height of the upwardly projecting lobes of the link.

17. An antiskid device comprising a tread link 5 

